1. Field of the Invention
This invention pertains to the general field of herbicides and more specifically to a new compound useful in controlling undesired plant growth.
2. Description of the Prior Art
The 1,2-dihydro-3H-pyrazol-3-one subclass of dihydropyrazolones, of which the compound of the present invention is a member, has been known and studied extensively for a number of years. An important area of use of pyrazolones of this type has been in medicine, where 1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one (antipyrine) and many of its analogs are employed for their analgetic, antirheumatic, antineuralgic and sedative properties. Herbicidal activity for one member of this subclass, 4-chloro-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazole-3-one, and certain of its salts has been disclosed in U.S. Pat. No. 3,092,483. The 2-phenyl compound of the patent, being a 2-aryl-4-chloro-1,2-dihydro-3H-pyrazol-3-one, is chemically distinct from the compound of the present invention, a 2-cycloalkyl-4-iodo-1,2-dihydro-3H-pyrazol-3-one. U.S. Pat. No. 3,092,483, which claims herbicidal activity for the 4-chloro-2-phenyl compound, does not teach or suggest herbicidal activity for 2-cycloalkyl derivatives, much less the superior herbicidal activity of the 2-cyclohexyl-4-iodo derivative.
The outstanding plant responses in selective preemergence and postemergence herbicidal activity of the compound of the present invention have not previously been reported or suggested in the art.